Leather cleaning composition



Patented Dec. 15, 1936 2,064,285 LEATHER CLEANING CGMPGSI'IEQN NoDrawing. Application November 5, 19%, Serial No. 751,577

2 Claims. (Cl. 8?-5) This invention relates in general to leather 8.3gallons of a 48% solution of U. S. P. potascleansers and moreparticularly to a cleaner for sium hydroxide are mixed with 57 gallonsof iron finished leather goods such as suede leather free oleic acid toform a soap containing an exjackets, cess of oleic acid. The soap isthen added to 8'75 The cleaning of soiled finished leatherparticugallons of hydrocarbon solvent having the ML larly leatherjackets has. in the past been a problowing characteristics:

lem with the dry cleaning industry owing to the wide variety of spotsand types of dirt with Arqmatlc content l or mums 60% whichthe leatherjackets became soiled Such Amhne 15 Distillation range 135 to 195 C.

10 substances as varnish, paint, blood, grease, milk et, cetera, oftensaturate the leather in places rendering their removal most difficult,even when prespotting with a strong solvent which often re- '70 gallonsof dipentene and 12.5 gallons of secmoves also the dye in the leather. Acommon ondary butyl alcohol are added to complete the Flash point.(Tagliaube open cup) plus or minus 100 F. i

practice is to submit the leather to the usual composition. The excessamount of oleic acid,

dry cleaning treatment with a suitable hydrodipentene, and alcohol, inaddition to adding decarbon solvent, frequently with a final operationsirable solvent qualities, aid in dissolving the poof scraping, e. g.with sandpaper, to remove spots tassium oleate in the solvent.

not taken out in dry cleaning. I From the standpoint of performance com-In the past, cleaned leather' jackets often plete solubility of the soapin the solvent is not emerged from the cleaning process with blue,essential, although where the product is to be m lavender, green or graystains in them which stored mutual solubility of all the ingredients iscannot be removed with the usual solvents. desirable in order to preventStratification, and

It is an object of this invention to provide a. corrosion of metalcontainers.

9 leather cleanser which will readily remove or The purity of the oleicacid is of importance, 9 soften spots of foreign substances on theleather. for I have found that the colored streaks 'ap-'= A furtherobject of the invention is to provide a pearing in dry cleaned leathergoods are the leather cleanser which will not remove the dye result ofreaction between chemicals remaining from the leather in appreciablequantities. A in the leather from the tanning process with furtherobject is to provide a cleanser which will small amounts of iron saltsso that as small a 0 not adversely affect cleaning solvent systems,percentage as .002% (as F6203) in theoleic acid into which some of the.cleanser is certain to will produce a discoloration of the cleaned pass.leather. Commercial shipments of white oleic Another object of thisinvention is to provide acid have contained iron in amounts varying aleather cleanser which will not produce 001- from 0.020.002% (as ream).

ored stains in the dry cleaned article. The fore- As a preliminary stepin the manufacture of going objects and other which will be apparmycomposition I remove the traces of iron soap cut, I prefer to accomplishwith a product obfrom theoleic acid by treatment with a small tained bymixing a given amount of alkali with amount of aqueous tannic acid,after which the an excess of iron free oleic acid to form an oleateaqueous liquor containing the iron as tannate [m with some free oleicacid present. The resulting is drawn off and the purified oleic acid iswater soap is then dissolved in a hydrocarbon solvent washed to removethe remaining tannic acid. having a relatively high percentage ofaromat- -By this means I have been able to reduce the ics, or achlorinated solvent such as carbon iron content of the oleic acid tosuch an extent $5 tetrachloride.

A small amountof pine oil, or pine oil derivaalthough it will of coursebe realized that it is tive such as dipcntene, or a low boiling alcoholpreferable to remove all traces of iron. may be added to the mixture asan additional While it is preferable to use a solvent with as solvent.high an aromatic content as possible, any per- The novel features that Iconsider charactercentage of aromatics over 20% will serve. While 50istic of my invention are set forth with particu- I prefer to use a.hydrocarbon fraction having larity in the appended claims. Theinvention, a high flash point, at the same time it is desirhowever,together with. advantages thereof will able to have a solvent .which hasan end point be best understood from the following descripsuificientlylow to permit. ready evaporation of tion of a specific example of mycleaner. the cleanser. It is obvious that other suitable that .my soapcontains less than .001% iron, 45

solvents might have a boiling from that given in the example.

The preferred method of using the cleanser is as follows: the leathergoods are run for a few minutes in a dry cleaning washer, containing oneof the usual cleaning solvents in order to remove loose dirt. Thesolvent is then wrung out of the leather goods which are next soakedrange different used as a soaking used as a prespotter or added to thecleaning 4 solvent.

My leather cleanser has been found to remove oil and grease spots and toloosen the gums and resins of many paints and varnishes as well as toremove blood, and water soluble spots produced by sugar solutions, jam,etc. My leather cleanser has been found more effective than when usingthe ingredients separately. example, while aqueous solutions can be usedstill! so that a supplemental treatment is necessary to restore thesuppleness to the leather. 0n the other hand, by the use of petroleumproducts alone, blood more permanently. leather cleanser effectivelyloosens the blood spots so that they are readily removed in the usualdry cleaning or, in case of resistant paint spots, etc., by brushing,after application of the cleanser and prior to rinsing in solvent.

Another advantage of my cleanser as before stated is that the formationof colored patches in the leather is prevented.

Although I have described certain specific tannic acid embodiments of myinvention, I am aware that modifications thereof are possible. While Ihave used my cleanser on leather understood that it may also be used asa cleanser for other materials.- The invention therefore is not to berestricted, except insofar as is necessary by the prior art and theappended claims.

I claim as my invention:

1. The process of preparing an improved leather cleaning compositioncomprising subjecting a substantially pure commercial oleic acid, whichcontains combined iron in a concentration sufficient to cause thediscoloration of leather cleaned with a cleanser containing adry-cleaning soap of said acid, to the chemical'action of underconditions to form iron tannate and to reduce the concentration of ironin said oleic acid to less than .001%, separating oleic acid containingless than .00l% iron from the iron tannate, saponifying the separatedoleic acid to form a dry-cleaning soap, and mixing said soap with adry-cleaning solvent. x

2. The process of preparing an improved leather cleaning compositioncomprising subjecting a substantially pure commercial oleic acidcontaining combined iron in a concentration of more than .00l% tothechemical action of tannic acid under conditions to form iron tannate andto reduce the concentration of iron in said oleic acid to less than.001%, separating the treated oleic acid containing less than .001% ironfrom the iron tannate, saponifying the separated oleic acid to form adry-cleaning soap, and mixing said soap with a dry cleaning solvent.

WALLACE J. YATES.

goods, it should be

